The present invention relates to mixtures with 1,1,1,3,3-pentafluorobutane (R 365 mfc) and their use for the manufacture of foamed plastics.
The use of partially fluorinated hydrocarbons as blowing agents for the manufacture of foamed plastics is already known. The international patent application WO 92/00345 discloses the use of partially fluorinated alkanes with 4 or 5 carbon atoms, which have a "tertiary structure", as blowing agents for the manufacture of polyurethane and polyisocyanurate foamed plastics.
The German Offenlegungsschrift DE 44 22 714 A1 discloses compositions, which contain 1,1,2-trifluoroethane, and the use of such compositions as blowing agents for the manufacture of foamed plastics. The international patent application WO 96/14354 discloses the manufacture of foamed plastics, for which a liquid blowing agent composition is used, which contains liquefied carbon dioxide under pressure. The blowing agent compositions may, moreover, contain fluorinated chlorinated hydrocarbons and fluorinated hydrocarbons, for example, also 1,1,1,3,3-pentafluorobutane (R 365 mfc). The German patent application 195 41 013 discloses, among other things, blowing agent compositions for the manufacture of highly resilient polyurethane foam. The blowing agent compositions comprise 50 to 95 parts by weight of 1,1,1,2-tetrafluoroethane and 5 to 50 parts by weight of 1,1-difluoroethane and/or readily volatile organic compounds. WO 96/12758 discloses blowing agent mixtures for the production of rigid polyurethane foams. The blowing agents may, if desired, contain fluorinated hydrocarbons such as 1,1,1,2-tetrafluoroethane, 1,1,1,3,3-pentafluoropropane, 1,1,1,3,3-pentafluorobutane, or 1,1,1,3,3,3-hexafluoropropane. The WO 96/30439 discloses azeotropic compositions comprising, among other things, 1,1,1,4,4,4-hexafluorobutane or perfluorohexane and certain C.sub.5 or C.sub.6 hydrocarbons. These compositions can be used as blowing agents for the manufacture of rigid polyurethane foams.